Code result
U0038
Vehicle Communication Bus B Performance
Moderate severity
What it means
Bus B is electrically OK but message rate or error counters are outside spec. Often intermittent wiring or a degraded transceiver.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Wiring chafed or marginal
highOne of the most commonly reported causes for this code — check this first.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
CAN terminating resistor (120 Ω) drifted out of spec
lowLess common, but worth ruling out after the more likely causes.
Related help
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